Pi4 fitting Kit just add 2-8gb Raspberry Pi4 board and any software you want.
ITX steel mount frame with rear panel
Geeek Pi HDMI adaptor board
ATX power lead cable, useful only with our ATX adapter.
Screw and spacers kit
A better kit is this one but needs SFX PSU.
Introduction and explanation video of Ami-Hybrid concept and power of setup